This GCHQ presentation from 2011 provides the background to the agency’s hacking attack on Belgacom: see the Intercept article Operation Socialist: The Inside Story of How British Spies Hacked Belgium’s Largest Telco, 13 December 2014. gchq-mobile-networks-in-my-noc-world

﻿TOP SECRET STRAP 2
Mobile Networks in
World
Head of GCHQ NAC
n/\c
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